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3.0 PERMANENT MONITORING WELL REPLACEMENT 3.1 Well Installation The well construction/installation specifications are similar to those used for the original wells except for several minor modifications which are described in the paragraphs below. The replacement monitoring wells will be installed as close as possible (within a radial distance of ten feet) to the original well locations and will be screened at approximately the same depths. Based on previous well installation experiences at the Site, mud rotary drilling techniques will be utilized. All drill cuttings returned to the surface will be stockpiled on plastic sheeting or within a plastic lined mudpit for disbursement or disposal pending receipt of the stockpiled soil sample analytical results. The installation of each monitoring well will be initiated by drilling a six-inch diameter pilot borehole to a depth of 5 to 10 feet greater than the original monitoring well's total depth. The pilot borehole will be logged by a registered geologist. The resulting log will be utilized by the supervising geologist for comparison to the original well logs. The pilot borehole will be reamed to a depth approximately 3 feet deeper than the depth of the original well. The replacement well will be constructed with a 6 foot silt trap at the bottom followed by 5 feet of 0.060 slot, low carbon, shaped, wire screen, followed by a 6 5/8 inch diameter, steel, blank casing extending to 1.5 feet above the ground surface. If the screened section intersects low permeable material (clay), the depth of the screen will be adjusted slightly to ensure groundwater capture from permeable aquifer materials as determined by the supervising geologist. The filter pack will consist of No. 21 gravel tremmied from the bottom to four feet above the screen section followed by one foot of #3 sand. A minimum 2 foot thick bentonite seal will be placed on top of the filter 5